Method for the manufacture of cellulose products



Patented Nov. 7, 1939 UNITED STATES PATENT ()FFiQE METHOD FOR THE MANUFACTURE OF CELLULOSE PRODUCTS Germany No Drawing. Application February 10, 1937, Serial No. 125,072. In Germany January 21, 1936 8 Claims.

It is known that cellulose materials of any form such as fibres, threads, ribbons, films, foils, plates, plastic masses and the like obtainable by precipitation from solutions of cellulose compounds such as nitrocellulose, acetylcellulose, benzylcellulose, ethylcellulose, and particularly from aqueous xanthogenate cellulose solutions, are of a small strength in wet state which often shows with threads only 50 to 60% of the strength in dry state.

Now it has been found, that with cellulose prod ucts of regenerated cellulose obtainable from xanthogenate-cellulose-solutions or likewise from cellulose-derivatives, we are in a position to attain an almost 100% wet strength (referred to the strength in dry state) in adding to the cellulose solutions, before working them up into the shaped material, furfurol or its homologues or derivatives, and particularly alcoholic hydrogenation products of the furfurol or their esters or ethers respectively.

Besides the furiurol also e. g. the methyl-furfurol, the furfuryl-alcohol, the tetrahydro-furfuryl-alcohol, the methyl-furfuryl-alcohol, are to be considered. Further one may apply the ethers and esters of those compounds as far as they are of an alcohol character such as e. g. the furfuryl-acetate, the tetrahydro-furfuryl-benzoate, the methyliurfuryl adipic acid ester, the fur furyl-butyl ether, the tetrahydro-furfuryl-dodecyl ether, the methylfurfuryl-oleyl ether, the methylfurfuryl-monoglycerol ether. Generally speaking the hydroxyl groups of the aforesaid compounds of an alcoholic character may be alkoxylated or esterified by organic residues containing 1 to 18 carbon atoms and eventually further substituents such as hydroXyl-groups, amino-groups and the like.

Besides the afore-cited products we are also allowed to co-employ other suitable substances such as naphthol, naphthol sulfonic salts, formaldehyde, carbamide and the like. For products made of aqueous xanthogenate-cellulose solutions there are, interalia, furfuryl-alcohol mixtures r with cresols such as metaor para-cresol or their derivatives, which are likewise apt for the purpose in question.

The additional amounts of the means according to the present invention are calculated on the amounts of cellulose or cellulose derivatives respectively present in these solutions and the respective proportion varies from approximate 0.2 to 10% but the most advantageous proportions lie between 0.5 and 2.5%.

Example 1 To an aqueous cellulose-xanthogenate solution which is to contain 6 to 7% of cellulose and approximately 6% of alkali one adds, just before the beginning of the spinning process, 1% of hydrogenated furfuryl-alcohol in a watery dissolution. This cellulose-solution is, in an acid spinning-bath, shaped in the usual way into threads or into any other material. The after-treatment is accomplished in the well-known manner in de-sulfurizing with sodium-sulfite and with subsequent washing, bleaching and finishing. The thus treated threads show a high wet strength of approximately 98% (referred to the dry strength).

Example 2 A mixture of 1 weight part of furfuryl-alcohol and 1 part of orthoor metaor para-cresol is added to an aqueous cellulose-xanthogenate-solution at the rate of 1 to 2% (referred to dry cellulose). It is recommendable to dissolve the said product in a solvent that itself is soluble in water. The working up of the cellulose-solution into shaped goods is done in the usual way. A shaped lace made with this solution from regenerated cellulose shows an excellent wet strength.

Example 3 To an aqueous cellulosexanthogenate-solution (viscose) of the usual concentration applied in the manufacture of cellulose hydrate films, one adds 2% of furfuryl-alcohol (referred to the cellulose) preferably in the form of an aqueous solution. The cellulose-xanthogenate-solution is worked up in the well-known way into cellulosehydrate-film on a film-pouring machine. The thus obtained film, when finished, is of an excellent fastness.

Example 4 3. Cellulose article consisting of regenerated cellulose containing a compound of the group consisting of furfurol, methyl furfurol, furfuryl alcohol, methyl furfuryl alcohol, furfuryl acetate, methyl furfuryl adipic acid ester, furfuryl butyl ether, methyl furfuryl oleyl ether, methyl i H furyl monoglycerol ether.

4. Cellulose article consisting of regenerated cellulose containing a compound of the group consisting of furfurol, methyl furfurol, furfuryl alcohol, methyl furfuryl alcohol, furfuryl acetate, methyl furfuryl adipic acid ester, iurfuryl butyl ether, methyl furfuryl oleyl ether, methyl furfuryl monoglycerol ether together with a compound of the group consisting of naphthol, naphthol sulfonic acid salts, and cresol.

5. Cellulose article consisting of regenerated cellulose containing a compound of the group consisting of furfurol, methyl furfurol, furyl alcohol, methyl furfuryl alcohol, furfuryl acetate, methyl furiuryl adipic acid ester, iurfuryl butyl ether, methyl furfuryl oleyl ether, methyl furfuryl monoglycerol ether together with formaldehyde.

6. Cellulose articles consisting of cellulosic material containing about 0.5 to 2.5% of the hydrogenation products of iurfurol.

'7. Cellulose articles consisting of cellulosic material containing between 0.2 and 10% of hydrogenation products of furfurol with a cresol.

8. Shaped articles consisting of regenerated cellulose containing hydrogenation products of furfurol.

JOHANN EGGERT. WALTER GELLENDIEN. 

